CVE-2022-28969 in AX1806
Summary
by MITRE • 05/06/2022
Tenda AX1806 v1.0.0.1 was discovered to contain a stack overflow via the shareSpeed parameter in the function fromSetWifiGusetBasic. This vulnerability allows attackers to cause a Denial of Service (DoS).
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Analysis
by VulDB Data Team • 05/11/2022
The vulnerability identified as CVE-2022-28969 affects the Tenda AX1806 router firmware version 1.0.0.1 and represents a critical stack overflow condition that can be exploited to execute a denial of service attack. This flaw exists within the web interface handling mechanism of the device, specifically within the fromSetWifiGusetBasic function where the shareSpeed parameter is processed without adequate input validation or bounds checking. The vulnerability stems from improper handling of user-supplied data that flows directly into stack-based memory operations, creating an exploitable condition that can be triggered through crafted HTTP requests to the router's web management interface.
The technical implementation of this vulnerability manifests as a classic stack buffer overflow where an attacker can supply excessive input data to the shareSpeed parameter, causing the program to overwrite adjacent memory locations on the stack. This occurs because the firmware fails to validate the length of input data before copying it into fixed-size stack buffers, a common weakness that aligns with CWE-121 Stack-based Buffer Overflow. The function fromSetWifiGusetBasic processes the shareSpeed parameter without implementing proper bounds checking or input sanitization, allowing maliciously crafted payloads to exceed the allocated buffer space and corrupt the stack memory structure.
From an operational perspective, this vulnerability presents a significant risk to network availability and service continuity as it enables remote attackers to remotely trigger a denial of service condition on the affected router. The attack requires no authentication and can be executed through standard web browser interactions with the router's management interface, making it particularly dangerous as it can be exploited by anyone with network access to the device. Once exploited, the stack overflow typically results in the router crashing and restarting, effectively denying network services to all connected devices and potentially requiring manual intervention to restore normal operation.
The impact of this vulnerability extends beyond simple service disruption as it represents a fundamental security flaw in the router's firmware design that could potentially be leveraged for more sophisticated attacks if additional vulnerabilities exist within the same codebase. Network administrators should consider this vulnerability in the context of the broader attack surface, as it may indicate poor input validation practices throughout the firmware that could expose other functions to similar exploitation. The vulnerability aligns with ATT&CK technique T1499.004 for network denial of service and could potentially be combined with other attack vectors to create more comprehensive compromise scenarios.
Mitigation strategies should focus on immediate firmware updates from Tenda to address the specific stack overflow condition, as well as network-level protections such as implementing access control lists to restrict web management interface access and deploying intrusion detection systems to monitor for exploitation attempts. Organizations should also consider network segmentation to limit the impact of potential exploitation and ensure that administrative access to such devices is restricted to trusted networks. The vulnerability demonstrates the importance of implementing proper input validation and memory safety practices in embedded firmware development, as outlined in industry best practices for secure coding and the NIST Cybersecurity Framework recommendations for critical infrastructure protection.